The present invention relates to foot warmers especially suited for use in cars and more particularly to foot warmers capable of warming drivers' feet or passengers' feet without excessively heating their heads.
There have been heretofore known two types as heating sources of car heating equipments, namely, one being a hot-water heating type and the other one being a exhaust steam heating type. The foot warmer of the present invention is directed to the former type.
Generally, in the hot-water heating type car heater system, a cooling water is heated by the engine and the heat of the coiling water is transferred to the air by a heat exchanger. The thus heated hot-air is blown from the nozzle of a car heater into the passenger compartment of a car.
Although conventional car heating arrangements, such as car heaters or car air-conditioners, emit hot-air heated well enough from their nozzle into a car passenger compartment, the air does not fully mix with cool air in the car. Thus, even if the temperature of the hot-air being blown from the car heater or air-conditioner is at high temperatures of 40.degree. to 50.degree. C., air in the car can not be uniformly heated. More specifically, the top or upper part of the car is undesirably excessively heated in a short time, while the lower part near the passengers' or drivers' feet can not readily be heated ro a required temperature. Thus, the known car heater or air-conditioner can not be considered ideal because of such disadvantageous phenomenon. Further, in a car, seats, passengers and so forth block the the convection of air. In addition, a car passenger compartment is surrounded with walls, and windows, allowing the escape or radiation of a large quantity of heat. These factors make it difficult to uniformly heat air in the car. If the rotating rate of a blower or fan and the quantity of hot air being blown off from a car heater are increased in order to increase the heating efficiency, unpleasant noise is not only increased, but also the increased noise gives a unwanted effect to specially equipped car audio system or the like. In addition, increasing the temperature of air blown from the nozzle of a car heater further increases the tendency to cause the above undesirable local excessive heating at the upper part, thereby only the part near the heads and faces of driver or passengers gets too hot, while the other lower parts near their feet are left cool. Thus, such conventional car heaters or car air-conditioners can not give satisfactory service and, particularly, in the case of a long-distance drive in a cold district in winter, great difficulties are presented.